The present invention relates generally to a navigational display system. More particularly, the present invention relates to a navigational display system which accepts user selectable waypoints. The navigational display system can be a graphical flight management system (FMS).
Navigational display systems are utilized in a variety of mobile applications to aid in the driving, piloting, or operation of various mobile platforms. Navigational display systems include a screen or monitor which displays a graphical representation of a map, flight plan, or route. Mobile platforms which utilize navigational display systems include airplanes, helicopters, cars, trains, boats, ships, vehicles, or other means of travel.
In one example of a navigational system, a graphical flight management system (FMS) includes a display and a joystick. The display provides a map including a navigational plan, such as, a graphical representation of a flight plan. The flight plan is often represented on the display by a line connecting various points along the expected route of travel.
Waypoints are often utilized on the navigational display so the operator can prepare for or execute particular maneuvers at particular points along the navigation plan. Waypoints can correspond to points or locations on a map. A waypoint is defined in a navigational database that is part of the flight management computer (FMC). An operator-defined waypoint is not defined in the navigation database and its specification is entered manually into the FMS by the operator or pilot.
An operator-defined waypoint can be generated by utilizing a joystick to manipulate a cursor on the display and by selecting the waypoint via a button once the cursor is over the desired location. In conventional navigational systems, such as, FMS, the display provides a graphical representation or map of the area surrounding the airplane. The present location of the airplane is represented by an airplane symbol at the center of the map. The display also provides a flight plan (e.g., represented as a solid line connecting points on the itinerary). The airplane is typically located on the flight plan.
The cursor is coupled to a center point of the map (the airplane symbol) via a dotted, rubberized line. A textual reading is provided next to the cursor which indicates a radial distance and angle from the center of the map. However, the reading can only provide a distance and angle reference with respect to the center of the map (airplane symbol). Once the waypoint is selected via a button, the flight management computer (FMC) of the flight management system converts the waypoint to a latitude/longitude coordinate pair which is displayed next to the waypoint. The latitude/longitude coordinate pair is not consistent with Air Traffic Control (ATC) phraseology.
In navigational applications, operator-defined waypoints are necessary in a number of situations. For example, in an avionics application, Air Traffic Control (ATC) often instructs a pilot to cross a point prior to a destination at a particular altitude. More particularly, a pilot my receive instructions stating xe2x80x9ccross 20 miles prior to Atlanta at 11,000 feet.xe2x80x9d To ensure compliance with the instruction, the pilot desires to define a waypoint on the flight plan 20 miles prior Atlanta. When the airplane reaches the waypoint, he or she is aware that the airplane should attain an altitude of 11,000 feet. Selecting such a waypoint requires time and skill when using the navigational system described above because the cursor only provides a reading referenced to the present aircraft position. Accordingly, the pilot must manually determine the location on the flight plan at which the airplane is twenty miles from Atlanta. The location can be computed by the FMS in response to user inputs on a textual user interface or a control and display unit (CDU). Thus, there is a need for an apparatus for and a method of defining a waypoint referenced to a point along a flight path.
In another example involving an avionics application, pilots may receive instructions in which particular actions or preparations should be made when the airplane reaches a particular point. For example, a pilot may have altitude restrictions when the aircraft reaches a particular distance and direction from a location. More specifically, pilots may have altitude restrictions when they reach 30 miles north of Cedar Rapids, Iowa. As discussed above, conventional systems require time and skill to create a waypoint at locations which are not referenced to the airplane.
Thus, there is a need for an apparatus for and a method of creating an operator-defined waypoint a particular direction and distance from a reference point either outside or within the flight plan. There is a need for a method of and apparatus for generating waypoints on aircraft navigational systems which are consistent with air traffic controller (ATC) phraseology. Further still, there is a need for an apparatus for and method of selecting a reference point or reference map object before creating a pilot-defined waypoint. Even further still, there is a need for an apparatus for and method of providing a textual readout in an along-track-distance format if the cursor or symbol is close to the flight plan or in a place/bearing/distance format if the cursor or symbol is away from the flight plan. Even further still, there is a need for an apparatus for and a method of automatically selecting the along-track-distance format or place/bearing/distance format depending upon the proximity of the symbol or cursor to the navigation plan.
An embodiment relates generally to a navigation system for an operator of a vehicle. The navigation system includes a display, a user interface, and electronic circuitry. The electronic circuitry is coupled to the user interface and the display. A reference point is selectable via the user interface. The display provides a textual reading related to a position of a symbol on the display with respect to the reference point. The position of the symbol is controlled via the user interface.
Another embodiment relates to a method of providing an operator-defined waypoint on a navigational display within a vehicle. The method includes steps of selecting a reference point on a navigational plan and displaying a reading related to a position of a symbol used to define the waypoint with respect to the reference point. The navigational plan is provided on the navigational display.
A further embodiment relates to a graphical flight management system for use in aircraft. The graphical flight management system includes means for displaying a flight plan, means for selecting a waypoint, and means for providing on the means for displaying a reading related to a position of a symbol used to select the waypoint with respect to a reference point.
Yet another embodiment relates to visual feedback for user actions and controls related to the creation of operator-defined waypoints on an interactive navigational map.